Respiratory System. Honors Biology. Facilitator: Mr. Lee Room 320

Transcription

1 Respiratory System Honors Biology Facilitator: Mr. Lee Room 320

2 Objectives Describe respiration Identify the function of the respiratory system Describe gas exchange

3 Introduction The respiratory system transports gases to and from the cardiovascular system The respiratory systems involves: External respiration- exchange of gases between the atmosphere and the blood Internal respiration- exchange of gases between the blood and the cells

4 Human Respiration System Exchanges oxygen and carbon dioxide between blood, air, and tissues The respiratory system consists of: Nose Pharynx (throat) Larynx (voice box) Trachea (windpipe) Bronchi Lungs Respiration 3D Medical Animation

5 Human Respiration System Nose: Air is warmed, moistened, and filtered before entering the lungs There are hairs lining the nasal cavity that trap large dust particles. Mucus moistens the air and traps dust and smoke

6 Human Respiration System Pharynx (throat): Passage way for both air and food The Larynx (voice box): Located on top of the trachea Trachea (windpipe): Epiglottis- flap of tissue that covers the trachea when you swallow Cilia sweep the trapped particles and mucus away from the lungs (to be either swallowed or spit out) At the lungs, branches into bronchi

7 Human Respiration System The Bronchi: Are two large passageways in the chest cavity Lined with cilia and mucus Each one leads to a lung

8 Human Respiration System In the lung, each bronchus subdivides into smaller bronchioles, and then to millions of tiny air sacs called alveoli Alveoli are grouped in clusters like grapes and are surrounded by capillaries

9 Gas Exchange The average healthy lung has over 150 million alveoli Oxygen dissolves in the moisture on the surface of the alveoli, and then diffuses through the capillaries Carbon dioxide diffuses in the opposite direction

10 Gas Exchange The air that you inhale usually contains 21% oxygen and.04% carbon dioxide The air you exhale usually contains less than 15% oxygen and 4% carbon dioxide 97 % of the oxygen moves into red blood cells Hemoglobin has four iron atom, each one can hold one oxygen molecule Most of the CO 2 reacts with water in plasma to form carbonic acid, and then bicarbonate ions

11 Mechanism of Breathing There are no muscles connected to the lungs The force that drives the air into the lungs comes from air pressure The lungs are sealed in two sacs called the pleural membranes inside the chest cavity At the bottom of the chest cavity is a large flat muscle called the diaphragm

12 Breathing As you breathe, the diaphragm contracts and the rib cage rises up making a partial vacuum, causing air to rush into the lungs Breathing is such an important function that your nervous system will not let you take complete control of it Inspiration- taking air into the lungs Expiration- releasing air out of the lungs

13 Breathing Controlled by the medulla oblongata Cells in its breathing center monitor the amount of carbon dioxide in the blood As CO2 level increases, nerve impulses from the breathing center cause the diaphragm to contract

14 Review Describe respiration: The respiratory system transports gases to and from the cardiovascular system The respiratory systems involves: External respiration- exchange of gases between the atmosphere and the blood Internal respiration- exchange of gases between the blood and the cells Identify the function of the respiratory system: Exchanges oxygen and carbon dioxide between blood, air, and tissues

15 Review Describe gas exchange: Oxygen dissolves in the moisture on the surface of the alveoli, and then diffuses through the capillaries Carbon dioxide diffuses in the opposite direction

16 Learn Long Live Long